CN1034980A - The thrust plate of topical surface treatment - Google Patents

Abstract

A kind of axial plunger hydraulic pump of the present invention and oil hydraulic motor thrust plate.The lubrication and seal end face of this thrust plate is done part surface again and is handled after conventional mechanical processing, the thrust plate of this processing can make the oil film of flow pair push power open to become opposite direction to change with gap thickness, thereby realize the hydrostatic pressure supporting, improve the operating life of thrust plate.With traditional liquid static-pressure support thrust plate parafacies ratio, simple in structure, cost is low.Be used for easily the conventional axial plunger machinery with the design of residual clamping force method is improved, can when reducing wear, keep less leakage rate.

Description

The thrust plate of topical surface treatment

The present invention relates to the design and the manufacturing of axial plunger hydraulic pump and oil hydraulic motor thrust plate.

For the working life of improving axial plunger hydraulic pump and oil hydraulic motor and the reliability of work, and minimizing power loss, in existing technical field, the secondary hydrostatic pressure that adopts of some axial plunger machinery flows is supported, concrete method has plenty of the continuous oiling of the restrictor of employing, has plenty of and adopts intermittently oiling etc.Adopt these methods not only to make the structure complicated of axial plunger machinery, and cost also sharply increase.

In order to overcome above-mentioned deficiency, be developed into a kind of thrust plate of topical surface treatment, the special the application that proposes.

The present invention proposes a kind of thrust plate that can make the supporting of the secondary generation automatically of flow hydrostatic pressure, the feature of this thrust plate is its lubrication and seal surface after finishing conventional mechanical processing, carries out one local surfaces chemical etching again and handles (or machining processes or electrolytic treatments) technology.This process of surface treatment makes processed surface produce certain average corrosion depth and makes surface one-tenth stepped shaft, or surface roughness is increased to some extent, or not only forms average corrosion depth but also surface roughness is increased.

The one dimension lubrication and seal pair of Fig. 1, an end face of topical surface treatment

One of layout of Fig. 2, end face topical surface treatment

Two of the layout of Fig. 3, end face topical surface treatment

Three of the layout of Fig. 4, end face topical surface treatment

The thrust plate of Fig. 5, topical surface treatment

For the ease of explaining that this thrust plate forms the principle of hydrostatic pressure supporting, elder generation is illustrated by one dimension lubrication and seal pair as shown in Figure 1, and expression is exaggerated in rough surface and gap among the figure in order to say something.The left side is the sealed fluid of pressure P, and right atrial pressure is zero.The standard deviation of the original surface roughness in upper-end surface (1) wherein ₁, in zone of high pressure P one side, width is to make its surface profile produce an average corrosion depth △ h=h through topical surface treatment on the zone of A ₂-h ₁, and make the standard deviation of its surface roughness that is corroded increase to σ ₂If sealed fluid is an incompressible fluid, surface roughness is isotropic, and the standard deviation of lower end surface (2) roughness is σ ₃But, then push power F open and be by average Reynolds equation derived unit length fluid film:

$\mathrm{F=P\; 〔}\frac{A}{2}+\frac{\mathrm{<figure-callout\; id="2"\; label="B"\; filenames="881008702\_DRIMG1.png"\; state="\{\{state\}\}">B</figure-callout>}}{2}\frac{{\phi }_2{\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="881008702\_DRIMG2.png,881008702\_DRIMG3.png"\; state="\{\{state\}\}">h</figure-callout>}}^3{}_2\mathrm{(B-A)}}{{\phi }_2{\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="881008702\_DRIMG2.png,881008702\_DRIMG3.png"\; state="\{\{state\}\}">h</figure-callout>}}^3{}_2{\mathrm{(B-A)+\phi }}_1{\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="881008702\_DRIMG2.png,881008702\_DRIMG3.png"\; state="\{\{state\}\}">h</figure-callout>}}^3{}_{1}A}〕$

Wherein:

h ₂＝h ₁+△h

φ ₁-low-pressure lateral pressure flow coefficient

φ ₂-high side pressure flow coefficient

The e-natural logarithm truth of a matter

h ₁-maximum mean gap

h ₂-minimum average B configuration gap

A-treatment surface width

B-lubrication and seal face width degree

Then to given A, B, σ ₁, σ ₂, σ ₃, △ h and P can obtain unit length and push power F and minimum average B configuration gap h open ₁Relation.If σ ₂=σ ₁, △ h=0 has just become not do the traditional lubrication sealing pair that etch is handled, and can get F by following formula _Conventional=(B)/2 P promptly pushes power open and does not change with the variation of seal clearance, just can not realize hydrostatic support so do not add compensator.Handle △ h＞0 then, σ if do the surface local chemical etching ₂＞σ ₁, in this case, if h ₁Much larger than △ h and σ ₂, h then ₂≈ h ₁, φ ₁≈ φ ₂≈ 1, and the power of at this moment pushing open is the same with the traditional lubrication sealing surface, i.e. F=F _ConventionalIf h ₁=0, F=1/2 (A+B) P=((A then)/(B)+1) F _Conventional, the power of promptly pushing open can increase to ((A)/(B)+1) that conventional seal lubrication pair pushes power open doubly.More than be h ₁Situation when two limit positions.Hence one can see that, between these two limit positions, the fluid film unit length push open power F will with minimum average B configuration gap h ₁Do the opposite variation of direction, thereby can realize the hydrostatic pressure supporting.

To given hydrodynamic pressure P, lubrication and seal face width degree B, original roughness parameter σ ₁, σ ₅And impacting force, suitably control corrosion depth △ h, roughness parameter σ ₂With treatment surface width A, can decrease and the difference requirement of sealing realize end face separating fully or the slight contact of end face on the minimal design gap respectively by anti-friction.

Fig. 2, Fig. 3, Fig. 4 are represented is the layout in the surface etching zone corresponding with Fig. 1, and cross hatch shown in Figure 2 zone (4) is for having done the surface of etch, and this layout is called basic layout, is not (3) by the surface of etch.Or in the cross hatch zone and not by the zone of not doing etch (5) of the surface of etch (3) communication, as shown in Figure 3.Or with the zone of in the cross hatch zone, not linked up of not doing etch (6) by the surface of etch (3), as shown in Figure 4.Or in the cross hatch zone and by the combination in the surface of etch (3) zone of not doing etch that link up and that do not link up.The common trait of these layouts is to handle and realize the hydrostatic pressure supporting effect by part lubrication and seal surface being carried out chemical etching.Basic layout shown in Figure 2 can obtain maximum hydrostatic pressure support effects.

Figure 5 shows that the layout in a kind of typical plane valving surface chemical etching zone, in high-pressure trough (8) two side areas (4) or its is zone (4) and zone (9) on every side, carrying out the local surfaces chemical etching again handles, the selection of all design parameters can be similar to the one dimension formula and try to achieve, and also can determine with more accurate formula or numerical computation method.

General design criterion is △ h and σ ₂Should with design minimum clearance h ₁Same magnitude.The ratio of treatment surface width A and lubrication and seal face width degree B is advisable between 0.3～0.95.What will select with relevant formula according to concrete designing requirement concrete value.

Topochemistry etch surface-treated technology can be with reference to the preparation process of printed circuit board (PCB) or the lithography corrosion process of intergrated circuit.According to the anticorrosion properties and the surperficial structure characteristics of different materials, be not difficult by suitably selecting for use corrosive liquid and concentration thereof and etch time to realize required corrosion depth △ h, roughness parameter σ ₂

Compare with other axial plunger machinery Port Plate Pair hydrostatic pressure support design schemes, the advantage of the application's valve plate is as follows:

(1) simple in structure, cost is low, makes easily.

(2) to adopting the conventional axial plunger machinery of residual clamping force design, it is about about 10～20% that the pressure force of its flow pair is pushed power open than oil film, just in time drops on thrust plate oil film of the present invention and push open in the regulation range of power.So can under the situation that does not change the original product design size, only increase by one chemical etching process of surface treatment and just can realize hydrostatic support.Thereby obviously improve the life-span and the reliability of existing approved product.

(3) can realize very little design gaps by the degree of control surface chemical etching, decrease the design alternative that obtains optimum between this a pair of contradiction requirement, when increasing life-span and reliability, keep less leakage rate in leakage rate and anti-friction.

Claims (3)

1, a kind of thrust plate of topical surface treatment, feature of the present invention is, the lubrication and seal surface of described thrust plate [7] is after the machinery of finishing routine adds, both sides in high-pressure trough [8], promptly promptly local surfaces chemical etching processing is carried out in zone [4] and zone [9] again around [4] or its of zone, make the certain layout of its local surfaces etch zone shape, the ratio of treatment surface width A and lubrication and seal face width degree B is between 0.3～0.95.

2, thrust plate according to claim 1, it is characterized in that, it is cross hatch zone (4) that local surfaces etch zone forms certain layout, or in the cross hatch zone and not by the zone of not doing etch (5) of the surface of etch (3) communication, or in the cross hatch zone with the zone of not doing etch (6) do not linked up, or the combination in zone (5) and zone (6) by the surface of etch (3).

3, thrust plate according to claim 1 is characterized in that, its local surfaces etch regional roughness is increased to some extent, or form certain average corrosion depth, or not only increase roughness but also form average corrosion depth.

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